The exams chaos in Scotland is deepening after it emerged that some pupils' incomplete Standard Grade results have been sent to the wrong schools.

Coatbridge High School in Lanarkshire received the results of candidates at Breadalbane Academy in Aberfeldy.

The Coatbridge pupils' grades went to St Margarets High in Livingston.

Some head teachers now fear the wrong information may have gone to every school in Scotland.

Opposition parties have renewed their calls for the resignation of Scottish Education Minister Sam Galbraith.

The Scottish Qualifications Authority has confirmed that nearly 4,264 Standard Grade results will have to be rechecked because they are inaccurate or incomplete.

The latest errors come on top of the massive problems with the Highers results and which claimed the resignation of the SQA's chief executive Ron Tuck.

The Conservatives' education spokesman Brian Monteith declared: "Surely this must be the final straw for Sam Galbraith as education minister.

Brian Monteith: "Final straw?"

"How many more blunders can he preside over before he does Scottish education a favour and falls on his sword?

"So long as Sam Galbraith is in place the reputation of our education system will continue to deteriorate.

"Meanwhile any remaining confidence that parents and pupils had that there would be a swift end to this crisis is evaporating fast."

The Scottish National Party said the 4,264 figure amounted to one in 12 Standard Grade results affected by the latest problems.

Education spokeswoman Nicola Sturgeon MSP said: "This is simply astonishing. New Labour have already seriously undermined the
credibility of Scotland's education system by being in charge of an unprecedented administrative and managerial Higher Still blunder.

Nicola Sturgeon: "Simply astonishing"

"Sam Galbraith is presiding over an education department in utter chaos.

"There is no doubt that his inability to run such an essential governmental department is costing
pupils and students needless anxiety and widespread disruption in schools.

"I don't think anyone can really believe what a shambles he has made of being education minister."

Mr Galbraith is expected to take the first opportunity to make a statement on the controversy when the Scottish Parliament reconvenes next week.

But the Tories and the SNP called for a three-hour debate or an extended statement from the under-fire minister when the cross-party bureau, which sets the parliamentary agenda, meets on Tuesday.